Griddle tops, such as those that are used for grilling foods, are typically electrically or gas heated and utilize a number of different types of constructions. Such griddle tops are usually fabricated from a steel or iron upper plate to provide a flat, durable and abrasion-resistant cooking surface. Because of the limited thermal conductivity of steel or iron, griddle tops typically provide a relatively even distribution of heat over the cooking surface only if the electrical or gas heating sources are positioned substantially evenly within or under the griddle tops. One type of griddle top construction uses a plurality of sub-plates or lower plates having cast-in electrical heating elements. The sub-plates are fabricated from a material that has a higher thermal conductivity than either steel or iron so as to more evenly distribute the heat from the electrical heating elements over the steel or iron upper plate. Additionally, the utilization of metal splash guards, typically attached by welding to the rear and side edges of a griddle top, results in the conduction of heat away from the edges of the upper plate, resulting in significantly lower cooking surface temperatures around the edges of the griddle top. Tests indicate that there is uneven distribution of heat over the cooking surface of presently available griddle tops, resulting in unevenly cooked foods and the possibility that harmful bacteriological contaminants within the food may not be thermally destroyed during the cooking process. Such tests also indicate that presently available gas heated griddle tops have a low thermal efficiency, typically less than 50%.
In view of the foregoing, it has become desirable to develop a griddle top that provides a substantially even distribution of heat over its cooking surface and wherein natural or LP gas-fired burners are utilized as the heat source.